Retaining element for building sheets

ABSTRACT

Disclosed is an elongate retaining element for building sheets, having in plane perpendicular to its direction of elongation, a head part which is substantially triangular in cross section. The head part including one or more movable rotationally symmetrical elements. The movable rotationally symmetrical elements are positioned at one or more vertices of the triangle. The head part includes one or more mountings in which the elements for engaging the building sheet are mounted. The mountings are attached to the head part by fixing elements.

The present invention relates to an elongate retaining element forbuilding sheets having as seen in cross section perpendicular to itsdirection of elongation, a head part for engaging at least one buildingsheet. The invention further relates to an assembly such a elongateretaining element engaging at least one building sheet member.

Such an elongate retaining element is known from GB-2167101-A, whichdiscloses a retaining element having a head part and a base partconnected by a connecting flange. The head part engages with the freeend of at least one building sheet, which is at least partially curvedover the head part of the retaining element. The head part issubstantially triangular in cross section and has rounded vertices thatengage with the building sheet.

A disadvantage of such prior art retaining elements is that movement ofthe building sheets over the retaining element, caused by e.g. thermalexpansion or wind suction, generates unpleasant noise.

One proposed solution to the problem of noise is proposed in GB-342933-Ain which the head part of the retaining element is provided with a solidcoating comprising an organic powder coating.

Another proposed solution is known from DE-4217221-A1 disclosing aholding element for use in roof constructions. The holding element isformed by a folded sheet with a curved end-section forming a head part.The head part co-operates via ball bearings or tapered wheels with aseparate member extending across the direction of elongation of theholding element. The building sheet member is flanged over this separatemember.

An object of the present invention is to provide an improved retainingelement. A further preferred object of the present invention is toprovide a retaining element that reduces the noise generated whenbuilding sheets when sliding in use over the head part of the retainingelement.

One or both of these objects are obtained by a retaining element havingin plane or as seen in cross section perpendicular to its direction ofelongation, a head part which is substantially triangular in crosssection, said head part comprising one or more movable rotationallysymmetrical elements, said elements being positioned at one or morevertices of the triangle, and characterised in that said head partcomprises one or more mountings in which the elements for engaging inuse the building sheet are mounted and in that the mountings areattached to the head part by fixing means.

The movable elements allow the engageable building sheet to slide overthe head part. The presence of movable elements in the head partsignificantly reduces the friction between the head part and theengageable building sheet enabling the building sheet to slide easilyover the head part of the retaining element without generatingsignificant noise. Wearing of the building sheet and the head part ofthe retaining element and resultant dust formation is also reduced. Afurther advantage is that reduced friction between the head part and thebuilding sheet reduces the mechanical load on the joint with a supportstructure. A high mechanical load on the retaining element isparticularly undesirable where the support structure to which aretaining element is attached is less robust such as for example,insulating glass wool or foam glass. By reducing the mechanical loadingto which the retaining element is subjected the present inventionreduces the risk of the retaining element failing. The movable elementsare rotatable to facilitate the sliding of a building sheet over thehead part. The movable elements are preferably rotationally symmetricaland can freely and smoothly rotate reducing the chance of noisegeneration as a building sheet slides over the head part of theretaining element. The head part comprises one or more mountings inwhich one or more movable elements are mounted. The mountings preferablyextend in the direction of elongation of the retaining element. Ofcourse the head part may comprise more than one mounting and eachmounting may contain multiple movable elements. The mountings facilitateassembly of a retaining element, as the movable elements do not have tobe individually mounted to the retaining element.

The head part of the retaining element is substantially triangular incross section and has a movable element positioned at one or morevertices of the triangle. The movable elements are therefore positionedon the head part at the points where a building sheet contacts the headpart and are thus optimally positioned to reduce the friction betweenthe head part and a building sheet sliding over the head part.

In an embodiment the movable elements are preferably spherical and canthus rotate in all orientations further reducing the chance of noisegeneration. The spherical movable elements preferably have a diameter ina range of 1 mm to 10 mm to ensure that they can be easily mounted onthe head part and effectively facilitate in use the sliding of abuilding sheet over the head part of the retaining element.

In an embodiment the movable elements are preferably made from metal,plastic or ceramic or a combination of these. Metal and ceramic are bothhard and resistant to wearing offering good durability whilst plasticsuch as PTFE (polytetrafluoroethylene) is easily formable and resistantto temperature variations. The metal used is more preferably sintermetal e.g. sinter bronze for increased hardness and wear resistance.

In an embodiment the retaining element preferably comprises a base partand a connecting flange connecting the base part and the head partwherein the head part, excluding the mountings and movable elements, thebase part and connecting flange are made from metal which can beextrusion formed or a combination of metal and plastic which provides aninsulating barrier between the interior of a roofing or claddingassembly and the building sheets for example as known from EP-1236840-A1(incorporated herein by reference). The head part, excluding themountings and movable elements, the base part and connecting flange arepreferably formed from extruded aluminium.

The retaining element known from international application WO-98/53158(incorporated herein by reference) may be provided with a head part asproposed in the present invention.

A further aspect of the invention relates to an assembly for roofing abuilding or cladding e.g. the façade of a building comprising one ormore elongate retaining elements as described above whereby the free endof at least one building sheet is flanged over the head part of theelongate retaining element engaging one or more of the movablerotationally symmetrical elements, and having the advantages as set outabove.

A further aspect of the invention relates to a mounting, in whichmovable elements are mountable, for use in the elongate retainingelement according to the present invention.

The present invention is described further by way of example withreference to the accompanying schematic drawings in which:

FIG. 1 shows a cross section perpendicular to the direction ofelongation through a retaining element according to the invention;

FIG. 2 shows a side view of a retaining element according to theinvention;

FIG. 3 shows a retaining element according to the invention engagingwith building sheets;

FIG. 4 shows a further retaining element according to the inventionengaging with building sheets;

FIG. 5A to 5C show a further retaining element according to theinvention in three different directions;

FIG. 6 show a mounting for holding bearings as used in the retainingelement of FIG. 5;

FIG. 1 shows a retaining element comprising a head part 1, a connectingflange 2 and a base part 3 where the connecting flange 2 connects thebase part 3 to the head part 1. The head part 1 of the retaining elementis preferably substantially triangular and comprises mountings 5 intowhich movable elements 4 in the form of ball bearings are mounted. Themovable elements could also be for example cylindrical or rugby-ballshaped. The movable elements may be made from metal, in particularsinter metal such as sinter bronze, plastic or ceramic. The mountings 5may be attached by snap-fitting or a lock nut or may be fixed withadhesive or other fixing means. The mountings may be made of plasticwhich provides an insulation layer between the building sheets and theconnecting flange and base parts of the retaining element and alsoresiliently retains the movable elements. The mountings may also be madefrom metal for durability. The head part of the retaining element,excluding the mountings and movable elements, the connecting flange andbase parts of the retaining element are preferably made from metal or acombination of metal and plastic. The head part of the retainingelement, excluding the mountings and movable elements, the connecting.flange and base parts of the retaining element are preferably made fromextruded aluminium.

FIG. 2 shows a side view of a retaining element according to theinvention. The numbering is in accordance with FIG. 1 as describedabove. It can be seen that the mountings 5 in which the movable elements4 are mounted preferably extend in the direction of elongation of theretaining element.

FIG. 3 shows a retaining element according to the invention and numberedin accordance with FIG. 1 as described above. The head part of theretaining element is substantially triangular in cross section. Theretaining element is engaging with building sheets 6 and 7. Buildingsheets 6 and 7 have upstanding flanges 6 a and 7 a respectively, whichend in curved portions 6 b and 7 b that curve around head portion 1 ofthe retaining element. The base part of the retaining element is mountedon a support structure 8 which can be for example a roof girder.

FIG. 4 shows a retaining element according to the invention and numberedin accordance with FIGS. 1 and 3 as described above. The head part ofthe retaining element is substantially triangular in cross section andcomprises cut away portions 10,11 adjacent the connecting flange 2 whichform grooves extending along the direction of elongation of theretaining element. The retaining element is engaging with buildingsheets 6 and 7 which have upstanding flanges 6 a and 7 a respectively.The upstanding flanges end in curved portions 6 b and 7 b that curvearound head portion 1 of the retaining element. The curved portions 6 band 7 b of the building sheets can extend into the cut-away portions orgrooves 10 and 11 which improve the engagement of the head part with thebuilding sheets. The base part of the retaining element is mounted on asupport structure 8 which can be for example a roof girder.

The retaining elements can of course also be mounted horizontally forexample as part of a wall cladding or façade assembly for a building, orat other angles from the vertical.

FIG. 5A shows another embodiment of the retaining element according tothe invention as seen in the direction of elongation. In the head part 1a mounting or holder is provided holding movable elements 4, preferablybearings and more preferably ball bearings, each bearing is located atthe vertices of a triangle. The mounting or holder is preferably made ofone single element, see FIG. 6. FIG. 5C shows a top view of theretaining element of FIG. 5A, in which there are providing threemountings each having three ball bearings 4. The mountings (not shown)are preferably arranged at regular intervals. In this embodiment threemountings are show, but it will be apparent to the skilled person thatthe retaining element should have one or more of such mountings withbearings, e.g. one, two, three, four, or more of the mountings could beinserted into the head part 1 of the retaining element. Each mountingwith the bearings is located in the head part of the retaining elementand is arranged in grooves or slots in the head part of the retainingelement. Such grooves are preferably substantially perpendicular to thedirection of elongation of the retaining element. Where the retainingelement is made from an extrusion, the grooves are preferably cut ormachined into the head part of the retaining element. The mountings arepreferably coupled to the retaining element to prevent sliding out inservice from the head part. Such a coupling could be achieved usinglocking means 11, for example a lock nut, applied through the head partof the retaining element. FIG. 5B shows a side view of the retainingelement of FIG. 5A.

FIG. 6 shows schematically a mounting 12 or holder which can be used inthe retaining element of FIG. 5. The bearings are fitted into themounting in recesses at the vertices. Preferably there is provided acentral bore for accommodating a lock for coupling the mounting in thehead part of the retaining element. Such a mounting 12 is preferablymade from a metal such as an extruded aluminium alloy or from a plasticmaterial, although other suitable materials may be used.

Having now fully described the invention, it will be apparent to one ofordinary skill in the art that many changes and modifications can bemade without departing from the spirit or scope of the invention ashereon described.

1. Elongate retaining element for building sheets, having in planeperpendicular to its direction of elongation, a head part which issubstantially triangular in cross section, said head part comprising oneor more movable rotationally symmetrical elements, said elements beingpositioned at one or more vertices of the triangle, wherein said headpart comprises one or more mountings in which the elements for engagingthe building sheet are mounted and in that the mountings are attached tothe head part by fixing means.
 2. Elongate retaining element accordingto claim 1, wherein the movable rotationally symmetrical elements arespherical.
 3. Elongate retaining element according to claim 1, whereinthe movable rotationally symmetrical elements are of diameter in therange of 1 mm to 10 mm.
 4. Elongate retaining element according to claim1, wherein the movable rotationally symmetrical elements are made frommetal, plastic or ceramic or combinations thereof.
 5. Elongate retainingelement according to claim 1, wherein the retaining element comprises abase part and a connecting flange connecting the base part and the headpart wherein the head part, excluding the mountings and movablerotationally symmetrical elements, the base part and connecting flangeare made from metal or a combination of metal and plastic.
 6. Elongateretaining element according to claim 1, wherein the fixing means forattaching the mounting to the head part comprise a snap-fitting, a locknut or adhesive.
 7. Assembly for roofing a building or forming abuilding façade comprising one or more elongate retaining elementsaccording to claim
 1. 8. Mounting, in which movable elements aremountable, for use in the elongate retaining element according toclaim
 1. 9. Elongate retaining element according to claim 2, wherein themovable rotationally symmetrical elements are of diameter in the rangeof 1 mm to 10 mm.
 10. Elongate retaining element according to claim 2wherein the movable rotationally symmetrical elements are made frommetal, plastic or ceramic or combinations thereof.
 11. Elongateretaining element according to claim 2, wherein the retaining elementcomprises a base part and a connecting flange connecting the base partand the head part wherein the head part, excluding the mountings andmovable rotationally symmetrical elements, the base part and connectingflange are made from metal or a combination of metal and plastic. 12.Elongate retaining element according to claim 2, wherein the fixingmeans for attaching the mounting to the head part comprise asnap-fitting, a lock nut or adhesive.
 13. Assembly for roofing abuilding or forming a building façade comprising one or more elongateretaining elements according to claim
 2. 14. Mounting, in which movableelements are mountable, for use in the elongate retaining elementaccording to claim 2.